Experimental Investigation of Membrane Materials used in Multilayer Surfacing Systems for Orthotropic Steel Deck Bridges

In the Netherlands asphaltic surfacings on orthotropic steel deck bridges (OSDB) mostly consist of two structural layers. The upper layer consists of what is known as very open porous asphalt (ZOAB) for noise reduction. For the lower layer Guss Asphalt (GA) is used. Earlier investigations have shown that the bonding characteristics of membrane layers to the surrounding materials have a very strong influence on the overall response of the steel bridge decks. Rijkswaterstaat, an agency of the Dutch Ministry of Infrastructure and the Environment, has commissioned Delft University of Technology to investigate and rank the performance of various commercially available membranes. In order to obtain insight into the response of membranes and their interaction with the surrounding materials on orthotropic steel decks, a project of evaluation of the performance of modern surfacing systems on OSDBs has been undertaken. Currently, there are various kinds of membranes provided by various companies. Thereby it was necessary to examine the bonding strength of these membrane products and to develop a ranking methodology. The research project focused on membrane performance and the effects hereof on the bridge deck as a whole. The methodology used was a multi-phase approach, which consisted of three main phases. In Phase 1, a Membrane Adhesion Test (MAT) device was developed at Delft University of Technology for the characterization of the adhesive bonding strength of membranes with the surrounding materials on OSDBs on the basis of a fundamentally sound, mechanistic methodology. Several membrane products were tested monotonically in this phase. In Phase 2, the MAT device was utilised for investigation of the fatigue response of the various membrane products on various substrates and under two different temperature conditions and three different cyclic load levels. A ranking methodology consisting of a combination of experimental (via MAT) and computational investigations was also developed and utilized for the ranking of the various membrane products. In Phase 3 of the project, four typical Dutch multilayer surfacing systems, constructed with five selected membrane products from Phase 1 and 2, were studied by means of five-point bending (5PB) beam tests and FE simulations. The findings of the 5PB beam tests were used for calibration and validation of the finite element predictions and for further ranking of the performance of the various membranes in Dutch OSDBs. On the basis of the project results, the top two ranking membranes were selected for subsequent testing by means of the LINTRACK facility available at Delft University of Technology.